U.S. patent number 8,292,409 [Application Number 12/933,671] was granted by the patent office on 2012-10-23 for ink jet head.
This patent grant is currently assigned to Konica Minolta IJ Technologies, Inc.. Invention is credited to Masato Ueda.
United States Patent |
8,292,409 |
Ueda |
October 23, 2012 |
Ink jet head
Abstract
Disclosed is an ink jet head exhibiting good assemblability
while protecting an electrode portion. An ink jet head (10)
comprising a head chip (2) including drive walls (22) and channels
(23) juxtaposed alternately with a drive electrode (25) being
formed on the drive wall (22), and a nozzle plate (24) wherein a
connection electrode is formed on the rear surface of the head chip
(2), a wiring board (3) on which an electrode portion (32) is
formed is bonded to project from the head chip (2), and ink in the
channel (23) is ejected by causing shear deformation of the drive
wall (22) is further provided with a holding member (5) disposed at
a position covering the electrode portion (32) and holding a
portion (31) of the wiring board (3) projecting from the head chip
(2), and an electrode portion protection member (4) bonded between
the holding member (5) and the electrode portion (32) using
adhesive and having a thickness in the range of 0.01-0.5 mm at a
part covering the electrode portion (32).
Inventors: |
Ueda; Masato (Akishima,
JP) |
Assignee: |
Konica Minolta IJ Technologies,
Inc. (Tokyo, JP)
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Family
ID: |
41113398 |
Appl.
No.: |
12/933,671 |
Filed: |
February 18, 2009 |
PCT
Filed: |
February 18, 2009 |
PCT No.: |
PCT/JP2009/052761 |
371(c)(1),(2),(4) Date: |
September 20, 2010 |
PCT
Pub. No.: |
WO2009/119190 |
PCT
Pub. Date: |
October 01, 2009 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20110018922 A1 |
Jan 27, 2011 |
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Foreign Application Priority Data
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Mar 27, 2008 [JP] |
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2008-083852 |
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Current U.S.
Class: |
347/69;
347/71 |
Current CPC
Class: |
B41J
2/1623 (20130101); B41J 2/1609 (20130101); B41J
2002/14491 (20130101); B41J 2002/14362 (20130101) |
Current International
Class: |
B41J
2/045 (20060101) |
Field of
Search: |
;347/69-71 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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2000-071448 |
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Mar 2000 |
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JP |
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2001-171122 |
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Jun 2001 |
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JP |
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2005-216242 |
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Aug 2005 |
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JP |
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Primary Examiner: Huffman; Julian
Assistant Examiner: Polk; Sharon A
Attorney, Agent or Firm: Holtz, Holtz, Goodman & Chick,
PC
Claims
The invention claimed is:
1. An ink jet head comprising: a head chip which comprises a drive
wall and a channel juxtaposed alternately, an outlet and an inlet
of the channel being arranged respectively at a front surface and a
rear surface of the chip, and a drive electrode formed on the drive
wall; a nozzle plate provided with a nozzle for ejecting ink, at a
corresponding position to the channel on the front surface of the
head chip; a connection electrode to electrically connect to the
drive electrode, formed on the rear surface of the head chip; and a
wiring board on which an electrode portion is formed for applying a
voltage from a drive circuit to the drive electrode via the
connection electrode, the wiring board being bonded to project from
the head chip in a direction perpendicular to a channel array
direction, wherein the ink jet head ejects the ink in the channel
from the nozzle by applying the voltage to the drive electrode to
cause a shear deformation on the drive wall, the ink jet head
characterizing in further comprising: a holding member disposed at
a position covering the electrode portion to hold a portion of the
wiring board projecting from the head chip; and an electrode
portion protection member bonded between the holding member and the
electrode portion by using adhesive, and having a thickness in the
range of 0.01 mm-0.5 mm at a part covering the electrode
portion.
2. The ink jet head described in claim 1, wherein the electrode
portion protection member is made of polytetrafluoroethylene or
polyolefin.
3. The ink jet head described in claim 2, wherein the drive wall is
made of a ceramic comprising leadzilconatetitanate.
4. The ink jet head described in claim 3, wherein the adhesive is
an epoxy type adhesive.
5. The ink jet head described in claim 4, further including a cap
member disposed in a periphery of an ink ejection surface of the
nozzle plate, wherein the holding member is provided between the
cap member and the electrode portion.
6. The ink jet head described in claim 3, further including a cap
member disposed in a periphery of an ink ejection surface of the
nozzle plate, wherein the holding member is provided between the
cap member and the electrode portion.
7. The ink jet head described in claim 2, wherein the adhesive is
an epoxy type adhesive.
8. The ink jet head described in claim 7, further including a cap
member disposed in a periphery of an ink ejection surface of the
nozzle plate, wherein the holding member is provided between the
cap member and the electrode portion.
9. The ink jet head described in claim 2, further including a cap
member disposed in a periphery of an ink ejection surface of the
nozzle plate, wherein the holding member is provided between the
cap member and the electrode portion.
10. The ink jet head described in claim 1, wherein the drive wall
is made of a ceramic comprising leadzilconatetitanate.
11. The ink jet head described in claim 1, wherein the adhesive is
an epoxy type adhesive.
12. The ink jet head described in claim 1, further including a cap
member disposed in a periphery of an ink ejection surface of the
nozzle plate, wherein the holding member is provided between the
cap member and the electrode portion.
Description
This application is the United States national phase application of
International Application PCT/JP2009/052761 filed Feb. 18,
2009.
TECHNICAL FIELD
The present invention relates to an ink jet head, and specifically
to an ink jet head having a structure for protecting an electrical
connecting section in a head chip.
BACKGROUND TECHNOLOGY
Regarding an ink jet head installed in an ink jet printer, an ink
jet head is conventionally known where a piezoelectric element is
provided to each nozzle for ejecting ink, and by making shear
deformation of this piezoelectric element an ink is ejected from
the each nozzle.
As one type of head chip to be used in this kind of ink jet head, a
head chip in which drive walls and channels are juxtaposed
alternately is commonly known.
In this type of head chip a drive electrode is formed for each
channel, and a connection electrode for connecting with the drive
electrode is formed on an upper surface of the head chip. On the
upper surface of the head chip, a wiring board which is formed with
an electrode portion corresponding to the connection electrode is
bonded such that the connection electrode and the electrode portion
are electrically connected (for example, refer to Patent Document
1).
By making the head chip to have this type of structure, an ink jet
head can be realized that is easy for manufacturing process, easy
for connecting the drive electrode with an external wiring, and
compact to lower the cost. Patent Document 1: Unexamined Japanese
Patent Application Publication No. 2006-82396.
DISCLOSURE OF THE INVENTION
Problems to be Solved by the Invention
In this type of the head chip, since the electrode portion formed
at the wiring board tends to be easily peeled off or broken away,
it is necessary to take a measure for preventing a stress on the
electrode portion.
In particular, in cases where the electrode portion is formed on
the wiring board made of a ceramic by aluminum evaporation and the
like, strength of bonding between the electrode portion and the
wiring board body is weak such that the electrode portion may be
peeled off by a small deformation, thus the electrode portion needs
to be protected.
However in cases of adopting the head chip of the above described
structure, since the distance between the electrode portion and
other member adjacent to the electrode portion is extremely small,
if it is tried to make the gap between the electrode portion and
the other member in order to prevent the stress being applied to
the electrode portion, an assembling work may become very
difficult.
Further, in a case of trying to coat a filling material for
protecting the electrode portion, the problem arises that it is
very difficult to coat the filling material thinly and without
generating pinholes and the like in a small gap between the
electrode portion and the other member.
In view of the above described points, objectives of the present
invention is to provide an ink jet head of easy assembling in
addition to protecting the electrode portion of the wiring
board.
Means to Solve the Problems
In order to solve the above described problems, an ink jet head
described in claim 1 is provided with: a head chip including a
drive wall and a channel juxtaposed alternately, an outlet and an
inlet of the channel arranged respectively at a front surface and a
rear surface of the chip, and a drive electrode formed on the drive
wall; a nozzle plate provided with a nozzle for ejecting ink, at a
corresponding position to the channel on the front surface of the
head chip; a connection electrode to electrically connect to the
drive electrode, formed on the rear surface of the head chip; and
wiring board on which an electrode portion is formed for applying a
voltage from a drive circuit to the drive electrode via the
connection electrode, the wiring board being bonded to project from
the head chip in a direction perpendicular to a channel array
direction; wherein the ink jet head ejects the ink in the channel
from the nozzle by applying the voltage to the drive electrode and
causing a shear deformation on the drive wall,
the ink jet head characterizing in further comprising a holding
member disposed at a position covering the electrode portion and
holds a portion of the wiring board projecting from the head chip;
and an electrode portion protection member bonded between the
holding member and the electrode portion by using adhesive, and
having a thickness in the range of 0.01-0.5 mm at a part covering
the electrode portion.
The ink jet head described in claim 2 is the ink jet head described
in claim 1, wherein the electrode portion protection member is made
of polytetrafluoroethylene or polyolefin.
The ink jet head described in claim 3 is the ink jet head described
in claim 1 or 2, wherein the drive wall is made of a ceramic
comprising leadzilconatetitanate.
The ink jet head described in claim 4 is the ink jet head described
in any one of claims 1-3, wherein the adhesive is an epoxy type
adhesive.
The ink jet head described in claim 4 is the ink jet head described
in any one of claims 1-4, further including a cap member disposed
in a periphery of an ink ejection surface of the nozzle plate,
wherein the holding member is provided between the cap member and
the electrode portion.
Effect of the Invention
According to the invention described in claim 1, 3, 4, or 5, in an
ink jet head having a very small gap between the electrode portion
and the other member adjacent to the electrode portion, by
disposing the electrode portion protection member in the gap
between the electrode portion and the other member adjacent to the
electrode portion, the electrode portion protection member may be
peeled off instead of the electrode portion in case of a stress
being applied to the electrode portion. Due to this, the broken
away of the electrode portion is protected, and generation of
disconnection in wiring can be prevented. Namely, the electrode
portion can be protected.
According to the invention described in claim 2, since the
electrode potion protection member is made of
polytetrafluoroethylene or polyolefin, an adhesion force of the
electrode potion protection member is weak. Therefore, the
electrode portion protection member may be firstly peeled off
instead of the electrode portion in case of a stress being applied
to the electrode portion. Due to this, the separation of the
electrode portion is protected, and breakage of wiring can be
prevented. Namely, the electrode portion can be protected.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view showing a total structure of the ink
jet head relating to the present embodiment.
FIG. 2 is an exploded perspective view of the inkjet head shown in
FIG. 1.
FIG. 3 is a section view of the inkjet head shown in FIG. 1.
FIG. 4 is an exploded perspective view showing a structure of main
part of the inkjet head shown in FIG. 1.
FIG. 5 is an exploded perspective view of the head chip relating to
the present embodiment.
EXPLANATION OF SIGNS
1: flexible substrate 11: bending portion 2: head chip 21:
substrate 22: drive wall 23: channel 24: nozzle plate 25: drive
electrode 3: wiring board 31: projection portion 32: electrode
portion 33: opening 4: electrode portion protection member 41:
opening 5: holding member 51: opening 52: bottom plate 53: side
wall 6: radiator plate 7: cap member 71: opening 8: manifold 81:
flow path connection section 10: ink jet head 20: chassis
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Hereinafter, embodiments of the ink jet head relating to the
present embodiment will be described, however the scope of
invention is not restricted with illustrated examples.
FIG. 1 shows a perspective view showing an external appearance of
the ink jet head relating to the present embodiment, FIG. 2 is an
exploded perspective view of the inkjet head shown in FIG. 1 and
FIG. 3 is a section view of the inkjet head taken on line III-III
of FIG. 1. FIG. 4 is an exploded perspective view showing a
structure of main part of the ink jet head shown in FIG. 1.
Wherein, XYZ axis common to all the above figures is shown in each
figure. As shown in FIG. 1 through FIG. 3, ink jet head 10 has a
chassis 20 open in upper and bottom surfaces. As shown in FIG. 3,
inside of chassis 20 assembled and arranged are flexible substrates
1, 1, head chip 2, wiring board 3, electrode portion protection
member 4, holding member 5, radiator plate 6, cap member 7,
manifold 8, etc., and cap member is provided on the bottom surface
of chassis 20.
Among them, flexible substrates 1, 1 are formed of plane substrates
as shown in FIG. 2, and arranged with a prescribed distance with
each other. On each of flexible substrates 1, 1 an unillustrated
drive circuit and the like are mounted. Further, on the lower end
portions of the flexible substrates 1, 1, bent portions 11, 11 are
provided to be faced as oppositely bent, and on the upper surface
of the bent portions 11, 11, wiring board 3 (described later) is
provided. And, in a space formed with a pair of flexible substrates
1, 1 and an upper surface of wiring board 3, manifold 8 (to be
described later) is provided. Further, the upper end portions of
flexible substrates 1, 1, are projected upward from the upper
surface of chassis 20.
Head chip 2 has a structure where drive wall 22 and channel 23 are
alternately arranged between two substrates 21, 21 as shown in FIG.
5. On the bottom surface (front surface) of head chip 2, provided
is nozzle plate 24 in which an ink ejection hole is arranged at a
position corresponding to each channel 23.
Here, drive wall 22 is formed of a piezoelectric element which
generates a deformation by applying a voltage. Commonly known
materials can be utilized as a piezoelectric material, while lead
zirconate titanate (PZT) is preferable.
On an inner wall of each channel 23 drive electrode 25, which being
a metal layer independent for each channel 23, is formed, and drive
electrode 25 is electrically connected to an unillustrated
connecting electrode formed on the upper surface of head chip 2 (a
surface facing to wiring board 3) for each channel 23.
Further, on the upper surface (rear surface) of head chip 2, wiring
board 3, which being connected to the above described flexible
substrate 1, 1, is bonded.
Wiring board 3 is formed with larger longitudinal and width sizes
compared to those of head chip 2, and has projection portion 31
which is protruded from head chip 2 in a bonded state with head
chip 2.
On lower surface of wiring board 3 (the surface facing to head chip
2), electrode portions 32 are formed with the same number and same
pitch as the connecting electrodes. Electrode portion 32 is
connected to the connecting electrode when wiring board 3 is
attached to head chip 2. Thus, electrode portion 32 is connected to
drive electrode 25 through the connection electrode.
Further, on wiring board 3, a rectangular opening 33 is formed
being elongated in the longitudinal direction (X direction).
Opening 33 is formed to be a size such that every opening of
channel 23 is able to be exposed. While, since opening 33 is made
to have a smaller surface area than the surface area of head chip
2, in the case of attaching wiring board 3 onto head chip 2, head
chip 2 is surely prevented from passing through wiring board 3.
Therefore, in the case of bonding wiring board 3 onto head chip 2,
wiring board 3 does not block off the opening of channel 23 while
contacting substrates 21, 21.
Wiring board 3 is formed of plastics or glass and the like having
low coefficient of thermal expansion. As wiring board 3, ceramics
such as non-polarized PZT or AIN can be used. Further, in order to
prevent the generation of deformation in head chip 2 caused by
difference of thermal expansion, materials having the difference of
thermal expansion coefficient of .+-.1 ppm or less can be
preferably utilized wiring board 3.
At the position where electrode portion 32 is formed on projection
portion 31, bending portions 11, 11 are attached, thus electrode
portion 32 of wiring board 3 and the drive circuit of flexible
substrates 1, 1 are electrically connected. Thus, signals from the
drive circuit of flexible substrates 1, 1 are enabled to be applied
onto drive electrode 25 on the inner wall of each channel 23 in
head chip 2 through bending portions 11, 11 and electrode portion
32 of flexible substrates 1, 1.
Further, in the under side of projection portion 31, electrode
portion protection member 4 is provided as shown in FIG. 4.
Electrode portion protection member 4 has opening 41 with the same
size as head chip 2, and head chip 2 is inserted in opening 41. In
this case, the upper surface of electrode portion protection member
4 covers electrode section 32 of wiring board 3 via bending
portions 11, 11. By this configuration, stress on electrode section
32 is eased. Electrode portion protection member 4 is adhered to
wiring board 3 by the use of epoxy-type adhesive.
As a material for electrode portion protection member 4, resins
with low adhesive property may be used, while the use of
polytetrafluoroethylene (PTFE) or polyolefin is preferable. By
utilizing the material with low adhesive property as electrode
portion protection member 4, in cases where stress of heat shock
and the like is induced on electrode portion 32, electrode portion
protection member 4 is made to be peeled off instead of electrode
portion 32.
Electrode portion protection member 4, has a thickness raging
within 0.01 to 0.5 mm at a portion of covering electrode portion
32. Namely, either the maximum or minimum values of the thickness
of electrode portion protection member 4 at the portion of covering
electrode portion 32 is designed to be within the above range. In
the present embodiment, electrode portion protection member 4
having approximately uniform thickness within the above range is
utilized.
Further, under the electrode portion protection member 4, holding
member 5 to hold projection portion 31 of wiring board 3 bonded
onto head chip 2 is provided.
Holding member 5 is configured to have bottom plate 52 formed with
a rectangular opening 51, and side wall 53 raising from both sides
of bottom plate 52 toward electrode portion protection member 4.
Bottom plate 52 has a width approximately same as wiring board 3,
and opening 51 is formed to be approximately same as nozzle plate
24.
Head chip 2 is set in opening 51, while wiring board 3 is placed on
the upper surface of bottom plate 52 of holding member 5.
Therefore, flexible substrate 1, 1 is also arranged inside of
holding member 5 and, flexible substrates 1, 1 and side wall 53 of
holding member 5 is made approximately in parallel.
Further, under holding member 5, tabular radiator plate 6 is
provided.
Radiator plate has opening 61 having the same size as nozzle plate
24, and head chip 2 is set in the opening 61 such that an upper
surface of radiator plate 6 contacts a bottom surface of holding
member 5.
Under radiator plate 6, cap member 7 is provided.
Cap member 7 is a rectangular plane plate and provided under side
of cassis 20.
In cap member 7, opening 71 which has the same size with nozzle
plate 24 is provided. Nozzle plate 24 is set in opening 7 such that
an ink ejection surface of nozzle plate 24 and a bottom surface of
cap member 7 are arranged in a same plane. In this way, since cap
member 7 is arranged in the periphery of ink ejection surface of
muzzle plate 24, breakage of the ink ejection surface of nozzle
plate 24, which may be caused by contact with other member, can be
prevented and head chip 2 is configured to be protected.
Although it is explained in the above description that an ink
ejection surface of nozzle plate 24 and a bottom surface of cap
member 7 are arranged in a same plane, "arranged in a same plane"
does not necessary mean an exactly same plane, but may be arranged
for example, such that the ink ejection surface of the nozzle plate
24 is arranged at a depressed position compared to the lower
surface of cap member 7, or a concave depression is formed in the
periphery of nozzle plate according to the size of opening 71.
Further, the surface of cap member 7 is made water-shedding, and
prevents the ink adhesion on the surface due to ink splash in case
of ejecting ink from head chip 2.
Further, cap member 7 may function as a suction lip to tightly
contact with a suction cap in a case of maintenance work of head
chip 2.
The maintenance work is for example a suction removal work that is
conducted in cases where an ejection hole is clogged due to
thickening or solidification of ink caused by evaporation of ink
solvent in the ejection hole at the time of image formation by
utilizing high viscosity ink, or the ejection hole is clogged due
to generation of air bubble of dirt in an ink flow path connecting
to the ejection hole.
At this time, the suction cap contacts cap member 7 in the
periphery of head chip 2 so as to cover the lower and surface of
head chip 2 where ink ejection hole being arranged, and a suction
pump connected to the suction cap sucks the ink and the like
remained in the ejection hole of nozzle plate 24 in head chip
2.
Manifold 8 is made in box shape having open bottom surface, being
disposed in the space formed with a pair of flexible substrates 1,
1 and the upper surface of wiring board 3, and keeping the ink
inside.
At right and left two positions on the upper surface of manifold 8,
flow path connection sections 81, 81 is dispose as shown in FIG. 2,
and to unillustrated ink supply pipes are connected to flow path
connection section 81.
Further, as shown in FIG. 3, manifold 8 is formed to be coincide
with the periphery of projection portion 31 of upper surface in
wiring board 3, thus an ink room common to all channel 23 is
formed.
Meanwhile, it is possible to interpose a heater and the like,
between cap member 7 and nozzle plate 24, for heating the ink
according to need.
Although in the present embodiment explained is that electrode
protection member 4 is fixed to wiring board 3 via flexible
substrates 1, 1, electrode protection member 4 may be directly
fixed to the exposed area of electrode portion 32 in the wiring
board 3. Further electrode protection member 4 only needs to be
fixed at a position covering electrode portion 32, for example may
be adhered on the upper surface of bottom plate 52 of holding
member 5.
Further, holding member 5, radiator plate 6, and cap member 7 may
be unified to form a holding member. In this case the holding
member functions as a radiator plate and a cap member.
Further, without providing radiator plate 6, holding member 5 and
cap member 7 may be unified to form a holding member. In this case
the holding member functions as a cap member.
Next, operations of the present embodiment will be explained.
In the ink jet head 10 structured as described above, by attaching
wiring board 3 on the upper surface of head chip 2, drive electrode
25 and electrode portion 32 of wiring board 3 are electrically
connected for each channel 23 of head chip 2.
When signals relating to ink ejection are sent to ink jet head 10,
the signals transfer from the wiring of flexible substrates 1, 1
through electrode portion 32 of wiring board 3, to the connection
electrode of head chip 2 and arrive to drive electrode 25. Thus,
drive wall 22 formed of piezoelectric element is shear deformed to
apply pressure to the ink in channel 23, and the ink is ejected
from the nozzle formed in nozzle plate 24.
Next, effect of the present embodiment will be explained.
In ink jet head of the present embodiment, by providing electrode
protection member 4 having weaker adhesion property than electrode
portion 32 between electrode portion 32 connected with bending
portion 11, 11 of flexible substrates 1, 1 and the member disposed
under the bottom face of electrode portion 32, in cases where heat
shock is imposed for example, electrode portion 32 is kept without
being peeled off since electrode protection member 4 is firstly
peeled off.
As described above, by providing electrode protection member 4
between electrode portion 32 and the member disposed under the
bottom face of electrode portion 32, and by firstly peeling off
electrode protection member 4 in the case where stress is applied
to electrode portion 32, the peeling off of electrode portion 32
can be prevented and generation of disconnection can be prevented.
Thus, electrode portion can be protected.
Further, by providing electrode protection member 4, in the case of
coating adhesive, the adhesive can be evenly coated due to the
surface contact between electrode protection member 4 and bending
portion 11, which leads to improve working efficiency.
EXAMPLE
The present invention will be described by using examples. However,
the present invention shall not be restricted by the examples.
Examples 1-5
As shown in Table 1 below, electrode protection members made of
PTFE having thickness of 0.05 mm-0.5 mm are mounted on the above
described ink jet head 10 in which the distance between the cap
member and the wiring board is arranged to be 1 mm or 2 mm. And,
the ink jet head was subjected to three cycle heat shock tests of
heating and cooling within the temperature range of -20.degree. C.
to 80.degree. C. After the heat shock test, conditions of wiring
connection were checked and evaluated as described below.
<<Evaluation>>
A: There is no generation of disconnection in the electrode
portion.
B: There are slight generations of disconnections in the electrode
portion.
C: There are generations of disconnections in the electrode
portion.
Comparative Examples 1-3
As shown in Table 1 below, electrode protection member made of PTFE
having thickness of 0.8 mm or 1.0 mm are mounted on the above
described ink jet head 10 in which the distance between the cap
member and the wiring board is arranged to be 2 mm or 3 mm. And,
the ink jet head was subjected to the same heat shock tests as the
above, and similarly evaluated.
Examples 6-8
As shown in Table 1 below, electrode protection member made of
polyethylene (PE) having thickness of 0.1 mm, 0.2 mm or 0.5 mm are
mounted on the above described ink jet head 10 in which the
distance between the cap member and the wiring board is arranged to
be 1 mm. And, the ink jet head was subjected to the same heat shock
tests as the above, and similarly evaluated.
Comparative Examples 4 and 5
As shown in Table 1 below, electrode protection member made of
polyethylene (PE) having thickness of 0.1 mm is mounted on the
above described ink jet head 10 in which the distance between the
cap member and the wiring board is arranged to be 1 mm or 2 mm.
And, the ink jet head was subjected to the same heat shock tests as
the above, and similarly evaluated. Wherein, in Comparative Example
4, holding member 5 and radiator plate 6 are not provided.
TABLE-US-00001 TABLE 1 Distance b/w cap Electrode member and
protection member wiring board Material Thickness [mm] [mm]
Evaluation Example 1 PTFE 0.05 1 A Example 2 PTFE 0.1 1 A Example 3
PTFE 0.2 1 A Example 4 PTFE 0.5 1 A Example 5 PTFE 0.5 2 A Comp.
Example 1 PTFE 0.8 2 B Comp. Example 2 PTFE 1.0 2 C Comp. Example 3
PTFE 1.0 3 B Example 6 PE 0.1 1 A Example 7 PE 0.2 1 A Example 8 PE
0.5 1 A Comp. Example 4 PE 1.0 1 C Comp. Example 5 PE 1.0 2 C Note:
Comp. Example means Comparative Example.
From the above result, generation of disconnection in the electrode
portion was not observed in cases of providing the electrode
protection member having thickness of 0.05 mm-0.5 mm, and
generation of disconnection was confirmed in cases of providing the
electrode protection member having thickness of 0.8 mm or 1.0
mm.
The electrode protection member having thickness of less than 0.05
mm is presumed to be effective, however in cases where the
thickness of the electrode protection member is less than 0.01 mm,
forming of the member may become difficult, and the thickness of
the electrode protection member is preferable in the range 0.01
mm-0.5 mm from a view point of practical usage.
Other than the above, the present invention is appropriately
changeable, being not restricted the above described
embodiments.
* * * * *